content/media/wave/WaveReader.h@97036ab72558
content/media/wave/WaveReader.h
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 #if !defined(WaveReader_h_)
7 #define WaveReader_h_
9 #include "MediaDecoderReader.h"
10 #include "mozilla/dom/HTMLMediaElement.h"
12 namespace mozilla {
13 namespace dom {
14 class TimeRanges;
15 }
16 }
18 namespace mozilla {
20 class WaveReader : public MediaDecoderReader
21 {
22 public:
23 WaveReader(AbstractMediaDecoder* aDecoder);
24 ~WaveReader();
26 virtual nsresult Init(MediaDecoderReader* aCloneDonor);
27 virtual bool DecodeAudioData();
28 virtual bool DecodeVideoFrame(bool &aKeyframeSkip,
29 int64_t aTimeThreshold);
31 virtual bool HasAudio()
32 {
33 return true;
34 }
36 virtual bool HasVideo()
37 {
38 return false;
39 }
41 virtual nsresult ReadMetadata(MediaInfo* aInfo,
42 MetadataTags** aTags);
43 virtual nsresult Seek(int64_t aTime, int64_t aStartTime, int64_t aEndTime, int64_t aCurrentTime);
44 virtual nsresult GetBuffered(dom::TimeRanges* aBuffered, int64_t aStartTime);
46 // To seek in a buffered range, we just have to seek the stream.
47 virtual bool IsSeekableInBufferedRanges() {
48 return true;
49 }
51 private:
52 bool ReadAll(char* aBuf, int64_t aSize, int64_t* aBytesRead = nullptr);
53 bool LoadRIFFChunk();
54 bool GetNextChunk(uint32_t* aChunk, uint32_t* aChunkSize);
55 bool LoadFormatChunk(uint32_t aChunkSize);
56 bool FindDataOffset(uint32_t aChunkSize);
57 bool LoadListChunk(uint32_t aChunkSize, nsAutoPtr<dom::HTMLMediaElement::MetadataTags> &aTags);
58 bool LoadAllChunks(nsAutoPtr<dom::HTMLMediaElement::MetadataTags> &aTags);
60 // Returns the number of seconds that aBytes represents based on the
61 // current audio parameters. e.g. 176400 bytes is 1 second at 16-bit
62 // stereo 44.1kHz. The time is rounded to the nearest microsecond.
63 double BytesToTime(int64_t aBytes) const;
65 // Returns the number of bytes that aTime represents based on the current
66 // audio parameters. e.g. 1 second is 176400 bytes at 16-bit stereo
67 // 44.1kHz.
68 int64_t TimeToBytes(double aTime) const;
70 // Rounds aBytes down to the nearest complete audio frame. Assumes
71 // beginning of byte range is already frame aligned by caller.
72 int64_t RoundDownToFrame(int64_t aBytes) const;
73 int64_t GetDataLength();
74 int64_t GetPosition();
76 /*
77 Metadata extracted from the WAVE header. Used to initialize the audio
78 stream, and for byte<->time domain conversions.
79 */
81 // Number of samples per second. Limited to range [100, 96000] in LoadFormatChunk.
82 uint32_t mSampleRate;
84 // Number of channels. Limited to range [1, 2] in LoadFormatChunk.
85 uint32_t mChannels;
87 // Size of a single audio frame, which includes a sample for each channel
88 // (interleaved).
89 uint32_t mFrameSize;
91 // The sample format of the PCM data. AudioStream::SampleFormat doesn't
92 // support U8.
93 enum {
94 FORMAT_U8,
95 FORMAT_S16
96 } mSampleFormat;
98 // Size of PCM data stored in the WAVE as reported by the data chunk in
99 // the media.
100 int64_t mWaveLength;
102 // Start offset of the PCM data in the media stream. Extends mWaveLength
103 // bytes.
104 int64_t mWavePCMOffset;
105 };
107 } // namespace mozilla
109 #endif
